126 THE MITOCHONDRIAL CONSTITUENTS OF PROTOPLASM. 



in the spermatozoon, which to my mind does not add any strength to his argument. 

 He found that there is a chemical change in addition to the change in position of 

 the mitochondria; for these mitochondria, which he styles "grains chromo])hiles," 

 are more resistant to insufficient fixation than the mitochondria in the rest of the cell. 

 Levi (1914, ]). 199) comes out definitely against this hypothesis, and Dues- 

 berg (1912, p. 752), on the ground of his own observations on the retinse of chick 

 embryos, is inclined to reserve judgment on the question. According to Levi, 

 the external segment is a cuticular formation and is not mitochondrial in nature, 

 and he cites some earlier work, which he already published in 1901, in support of 

 ■this conclusion. He worked on Triton larvae and his observations do not tally 

 with those of Leplat, yet both may be correct, because we can not take the posi- 

 tion that the retinal elements in widely different forms originate in precisely the 

 same way. We must try not to assume an altogether ultracritical attitude. The 

 evidence presented appears to be fairly conclusive that, in the bird at least, the 

 envelope of this external segment is mitochondrial in origin, for it is certainly 

 lipoidal and chemically resembles mitochondria to some extent. We can not regard 

 it as a direct transformation, however. 



THE "RANDREIFEN" OF AMPHIBIAN RED BLOOD-CORPUSCLES. 



Meves (1905, p. 103) advanced the view that this fine peripheral network, 

 just within the cell-membrane, results from the coalescence of individual mito- 

 chondria. He based this conclusion upon the similarity which he found in the 

 staining reactions of this network and the mitochondria by his iodic-acid and 

 malachite-green method. This is to be regarded merely as a suggestion until the 

 material has been worked out more carefully with adequate methods of technique. 



EOSINOPHILIC GRANULATIONS IN LEUCOCYTES. 



According to Ehrlich, the granulations which he described in blood-cells are 

 a true product of the secretory activity of the cells themselves. Meves (19106, 

 p. 656) concludes that these granules, just like those of gland-cells, arise from 

 mitochondria, and he forwards the additional argument that the eosinophile cells 

 of the salamander contain few if any mitochondria, the assumption being that the 

 mitochondria have all been transformed into the granules. It is unnecessary to 

 point out how loose this reasonmg is. I have studied the mitochondria in living 

 human polymorphonuclear leucocytes stained vitally with janus green and have 

 found no indication at all of transitions between the mitochondria and the specific 

 granulations. In fact, they are entirely distinct, (1) on the basis of the high 

 refractive index of the eosinophile granules, the low refractive index of the mito- 

 chondria; (2) the large size and spherical shape of the granules, the small size and 

 rod-like shape of the mitochondria; and (3) the lack of coloration of the granules 

 and the intense specific staining of the mitochondria. Moreover, I have examined 

 the eosinophihc myelocytes in the bone marrow of the guinea-pig, both vitally 

 stained with janus green as well as in fixed and stained preparations, without find- 

 ing any trace of a transition between the mitochondria and the granules. Neither 

 have I been able to find any indication of a transition between the mitochondria 

 and the neutrophilic or basophilic granulations in man. 



